Synthetic material tape or strip



July 25, 1967 J, HUREAU SYNTHETIC MATERIAL TAPE OR STRIP 2 Sheets-Sheet1 Filed Dec. 19, 1963 ooooooaoo FIG 4 July 25, 1967 J, HUREAU 3,333,039

SYNTHETIC MATERIAL TAPE OR STRIP Filed Dec. 19, 1963 2 sneets-sffieet 2h ,l4 W V L I T r I v v v I FIG. 4

FIG. 5

, INVENTOR. JACQUES HUREAU United States Patent 3,333,039 SYNTHETICMATERIAL TAPE 0R STRIP Jacques Hureau, Paris, France, assignor, by mesneassignments, to Wood Conversion Company, St. Paul, Minn, a corporationof Delaware Filed Dec. 19, 1963, Ser. No. 331,702 Qlairns priority,application France, Dec. 20, 1962, 919,290 2 Claims. (Ci. 264--146) Thisinvention relates to a synthetic material tape or strip that has greatdimensional stability, particularly when subjeced to heat, and that canbe used for reinforcing or stiffening certain parts of garments, such asthe waist-bands of trousers and skirts, the collars of shirts, and formany other purposes.

It is known to make cloth tapes for stiffening the waistbands of skirts.When made of natural threads or fibres, these known cloth tapes sufferfrom the drawback that they generally tend to shrink when washed and, asa general rule, tend with time to vary in length, and to an extentdifferent from the dimensional variations of the garments on which theyare fitted. This is due, inter alia, to the fact that these cloth tapesbecome desized after being washed a few times, as a result of which theyalso lose their stiffness. It is also known to make for the same purposecloth tapes woven from synthetic fibre threads, for example nylon, whichdo not suffer from the above drawbacks. The cost price of thesesynthetic fibre tapes, however, is high as their manufacture requirestwo successive operations, the first being a spinning operation and thesecond being a weaving operation. For reinforcing or stiffening certaingarment parts, for example shirt collars, it has also been proposed touse full-tapes of synthetic material, for example nylon, which can bemanufactured in a single piece by continuous extrusion. These knowntapes however prevent the passage of sweat therethrough. Moreover, theysuffer from bad dimensional stability when heated, a most bothersomedrawback when heat pressed between two pieces of cloth to formstiffeners.

The tape according to the invention is of the type set forth initiallyand has none of the drawbacks mentioned above of tapes used hitherto forthe above specified purposes; the tape is characterized in that itconsists of a strip of synthetic material formed over its entire surfacewith small, very closely spaced openings.

The tape according to the invention has great dimensional stability,particularly during the various treatments, including heat treatments,to which the garment on which it is mounted is subjected. Thedimensional stability during heating of the reinforced tape according tothe invention is due, inter alia, to the fact that the constituentsynthetic material flows or expands when softened into the smallopenings which as a result become smaller still without however becomingstopped up, whereas the flow or expansion of a full tape or ribbonwithout openings can only result in an increase of its length or width.This feature is particularly advantageous for producing stitfeners byheat pressing a strip of synthetic material between two pieces of cloth.Such a stiffener moreover allows perspiration to pass therethrough.Since it is formed with small and closely spaced openings over itsentire surface, the tape according to the invention may be madesufficiently thick to provide both substantial mechanical resistance,particularly to tearing, and suitable ilexibility. Furthermore, thepossibility of manufacturing the foraminous tape according to theinvention in a single continuous extrusion operation, by resorting to aknown method and to a known machine, makes it possible to produce thistape more cheaply than known tapes of woven synthetic fibres. Themanufacture of these ice known tapes requires two successive operations,the first being a spinning operation and the second being a weavingoperation.

An embodiment of the tape according to the invention and a method ofmanufacturing the tape will now be described by way of example withreference to the accompanying diagrammatic drawings in which:

FIG. 1 is a perspective view of a heated templet used for finishing theedges of the tape shown in FIG. 2;

FIG. 2 is a plan view of a tape according to the invention;

FIG. 3 is a sectional view of a first machine for manufacturing the tapeof FIG. 2;

FIG. 4 is a view from below of a second machine for.

manufacturing the tape of FIG. 2; and

FIG. 5 is a sectional view taken along line V--V of.

FIG. 410oking in the direction of the arrows.

The tape according to the invention illustrated in FIG- URE 1 consistsof a strip 1 of synthetic material having over its entire surface smalland very closely spaced openings 2. The thickness of the strip 2 and thed mensions and the spacing of its openings 2 depend on the stiffness andthe mechanical resistance, in particular totearing, that the tape isrequired to have for the uses to which it is to be put. In theillustrated embodiment, the openings 2 are of substantially oval shapeand are aligned in longitudinal and transverse rows. This arrangement,however, is optional since it is only tied to the method that isresorted to for manufacturing the foraminous tape,

as explained below. The tape illustrated in FIGURE 2 can for example beused to line trouser or skirt waist-- ing to the invention can also beused for many otherpurposes. They may for example be used in thehatmaking industry, in the shoe-making industry, in the morocco-leatherindustry (in particular for belt-making), and in the manufacture ofpassementerie (braid, stripes, etc.). They can also have technical uses,for example as endless bands which can be used as transmission belts forpulleys, pinions (in particular chain driven pinions), studded wheelsand cylinders, etc.; as perforated conveyor belts, such as those used inthe chemical, food and papermaking industries, and as strengthening orsupporting members.

There are several known methods forcontinuously extruding foraminoussheets of synthetic material, in particular sheets that are foraminousover their entire surface. Sheets of this kind, formed with fine andvery closely spaced openings can obviously be cut up into severalstrips, according to the invention, of suitable width. The machineswhich have been designed for carrying out these known methods generallyextrude continuously synthetic material tubes having walls that areforaminous over their entire surface. Tubes so obtained can also easilybe cut up lengthwise to produce several foraminous tapes or strips,according to the invention, of suitable width. Since, however, themachines required to carry out these known extrusion processes are moreor less complex and costly depending on the method it is proposed touse, the most economic conditions for continuously extruding sheets ortubes that are foraminous over their entire area and that can be cut upinto several tapes or strips according to the invention, can be had byresorting, inter alia and in particular, to the method and to one of themachines disclosed in my US. Patent 3,252,181 filed on Dec. 18, 1961.The machines disclosed in this patent comprise at least one die forcontinuously extruding a full sheet or tube of synthetic material andmeans for temporarily and locally preventing the synthetic material fromissuing from the die at those locations where the sheet or tube is to beformed with openings. The foraminous tape according to the inventionthat is illustrated in FIGURE 2 and which is formed with openings 2aligned both in the longitudinal and transverse directions, has beenobtained by cutting up a tube of synthetic material, perforated over itsentire surface and produced by continuous extrusion with a machine suchas illustrated in FIGURES 12 and 13 of the above referred to U.S. Patent3,252,181; the cutting up operation having been carried out along twogenerating lines of the cylindrical extruded tube, after cooling of theconstituent synthetic material, as illustrated in FIG. 3 in thisapplication; in FIG. 3 a full tube of synthetic material is extrudedthrough a circular slot 8 in a cylindrical die member 9; an annularmember 10 is reciprocated along the peripheral surface of die member 9,as indicated by the arrow 11, between a lower end position, in whichsynthetic material is temporarily and locally prevented from issuingfrom the circular slot 8 by teeth projecting from the lower end of saidannular member 10 through said circular slot 8, and an upper endposition in which the annular slot 8 is clear of said teeth of theannular member 10 and a full tube T is extruded therethrough; a doubleknife 12 is fastened to the lower end of die member 9, and is disposedalong a diameter of the cylindrical extruded tube T for cutting up thesame along two of its vertical generating lines, thereby .giving twoseparate foraminous tapes like that shown in FIG. 2.

A foraminous tape according to the invention can also be obtained bycutting up, along two of its parallel generating lines, a foraminoustube of synthetic material having a wall with openings over its entiresurface and extruded in continuous manner by some other method and someother machine of known type; the openings of the tape could then bedistributed, in relation to the longitudinal edges, in a mannerdifferent from that shown in FIG. 2.

When a foraminous tape according to the invention is obtained by cuttingup a sheet or tube of greater area, the longitudinal edges of the tapealways has rough edges which can be bothersome for the subsequent use towhich the tape is to be put. FIGURE 1 illustrates a device for smoothingthe roughness along the edges of the tape 1 obtained by cutting up apart of greater area. This device essentially consists of a templethaving two gauging members 3' and 3" arranged parallel to one anotherand at a distance slightly less than the width tape 1 is to have afterremoval of the asperities along its sides. These gauging members 3' and3" are heated to a temperature close to the softening point of thesynthetic material of which tape 1 is made, by known means, as forexample by electrical resistances 4' and 4", which extend lengthwisetherein in the vicinity of the oppositely lying faces of the gaugingmembers 3 and 3". The latter moreover are formed with V-shaped grooves7' and 7" in which pass the edges of tape 1 which is moved along a flatsupport 6 in the direction of arrow 5, so that the asperities along itsedges, by rubbing against members 3' and 3", become softened, and thematerial constituting these asperities becomes spread along the edges ofthe tape thereby smoothing these edges. The flat support 6, which doesnot contact members 3' and 3", can moreover be cooled by any knownmeans,

The known methods and machines referred to earlier can easily be adaptedfor the continuous extrusion of a single Width of foraminous tapeaccording to the invention, thereby avoiding the need for a subsequentcutting operation of a sheet or tube of greater area. This isillustrated in FIGURES 4 and 5, which correspond to FIGURES 21 and 22 ofmy Patent 3,252,181; a full sheet of synthetic material is extrudedthrough a rectilinear slot :13 in a outer die member 14; an inner diemember 15 is reciprocated within a recess inside of said outer diemember 14, as indicated by the arrow 16, between the shown end position,in which synthetic material is temporarily and locally prevented fromissuing from the rectilinear slot 13 by teeth 17 projecting from oneface of inner die member 15 through said rectilinear slot 13, andanother end position in which rectilinear slot 13 is clear of said teeth17 of the inner die member 15, and a full sheet S is extrudedtherethrough. The same advantage may be had, but with a considerableincrease in output, by permanently obturating locally the outlet of thedie of the machine disclosed in my above-mentioned U.S. Patent 3,252,181by means of stoppers, preferably equidistantly spaced, so assimultaneously to produce several tapes, of preferably equal width,according to the invention. This arrangement makes it unnecessarysubsequently having to cut up a sheet or tube of great rr area intoseveral tapes and having to smooth the amerities along the edges of eachtape so out What is claimed is:

:1. A method of producing foraminous strips of synthetic material bymeans of an extruder including dies, comprising the steps ofcontinuously extruding a tube of synthetic material, the circumferentialwidth of which is substantially a multiple of that of the foraminousstrip to be obtained; of forming openings in said tube by temporarilyand locally preventing the synthetic material from issuing from said dieat those locations Where the tube is to be formed with openings; ofcutting up the extruded and foraminous tube into a plurality of stripsof suitable Width thus creating asperities along the edges of saidstrips; and of smoothing the lateral asperities along the edges of eachof said strips by passing each of said strips through a constraining andheating templet to constrain the edges against movement other thanlongitudinally with the strip passing through said templet Whilesimultaneously heating said asperities to the softening temperature ofthe synthetic material constituting each said strip.

2. A method according to claim 1, further comprising the steps ofstretching said tube in at least one direction, and solidifying saidtube prior to cutting and smoothing.

References Cited UNITED STATES PATENTS 1,323,212 11/1919 Bulley 156-882,535,029 12/1950 Atamasoff et al. 156-88 2,582,777 l/1952 Grozinger16l109 3,019,483 2/ 1962 Schultheiss.

3,137,611 6/1964 Krolik l61l09 3,172,154 3/1965 Martin et al.

3,227,184 1/1966 Anderson et al 16l-109 EARL M. BERGERT, PrimaryExaminer.

D. J. DRUMMOND, Examiner,

1. A METHOD OF PRODUCING FORAMINOUS STRIPS OF SYNTHETIC MATERIAL BYMEANS OF AN EXTRUDER INCLUDING DIES, COMPRISING THE STEPS OFCONTINUOUSLY EXTRUDING A TUBE OF SYNTHETIC MATERIAL, THE CIRCUMFERENTIALWIDTH OF WHICH IS SUBSTANTIALLY A MULTIPLE OF THAT OF THE FORAMINOUSSTRIP TO BE OBTAINED; OF FORMING OPENINGS IN SAID TUBE BY TEMPORAILY ANDLOCALLY PREVENTING THE SYNTHETIC MATERIAL FROM ISSUING FROM SAID DIE ATTHOSE LOCATIONS WHERE THE TUBE IS TO BE FORMED WITH OPENINGS; OF CUTTINGUP THE EXTRUDED AND FORAMINOUS TUBE INTO A PLURALITY OF STRIPS OFSUITABLE WIDTH THUS CREATING ASPERITIES ALONG THE EDGES OF SAID STRIPS;AND OF SMOOTHING THE LATERAL ASPERITIES ALONG THE EDGES OF EACH OF SAIDSTRIPS BY PASSING EACH OF SAID STRIPS THROUGH A CONSTRAINING AND HEATINGTEMPLET TO CONSTRAIN THE EDGES AGAINST MOVEMENT OTHER THANLONGITUDINALLY WITH THE STRIP PASSING THROUGH SAID TEMPLET